000 AXPZ20 KNHC 110238 TWDEP TROPICAL WEATHER DISCUSSION NWS NATIONAL HURRICANE CENTER MIAMI FL 0405 UTC SAT OCT 11 2014 TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND METEOROLOGICAL ANALYSIS. BASED ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 0230 UTC. ...TROPICAL LOWS AND WAVES... A BROAD LOW PRESSURE CONTINUES TO MEANDER WITHIN THE MONSOON TROUGH NEAR 12N91W AND IS ESTIMATED AT 1007 MB. SCATTERED MODERATE ISOLATED STRONG CONVECTION FLARED EARLIER NEAR AND E OF THE CENTER...BUT HAS SINCE DISSIPATED. CYCLONIC 10-15 KT WINDS CONTINUE WITHIN ABOUT 150 NM OF THE CENTER WITH SEAS OF 4-6 FT. THIS LOW PRESSURE IS FORECAST TO CONTINUE MOVING SLOWLY NORTHWESTWARD REACHING NEAR 11N91.5W ON SAT WITH THE CYCLONIC WINDS GRADUALLY INCREASING TO 15-20 KT WITHIN 120 NM OF THE CENTER. THE LOW IS FORECAST TO THEN DRIFT SLOWLY W REACH NEAR 11N92W ON SUN WITH THE RADIUS OF 25-20 KT WINDS EXPANDING OUTWARD TO ABOUT 180 NM FROM THE CENTER WITH SEAS BUILDING TO 6- 8 FT IN MIXED WIND WAVE AND LONG PERIOD CROSS EQUATORIAL SW SWELL MAINLY OVER THE SE SEMICIRCLE ON SUN NIGHT. CONDITIONS WILL GRADUALLY BECOME MORE FAVORABLE FOR STRENGTHENING BY THE MIDDLE OF NEXT WEEK...WITH TROPICAL CYCLONE FORMATION POSSIBLE...AS THE LOW DRIFTS W TO NEAR 12N92W ON MON...NEAR 12N93W ON TUE AND NEAR 12N94W ON WED. A WEAK TROPICAL WAVE IS ANALYZED TO THE N OF 14N ALONG 109W AND HAS BEEN MOVING W AT 10 KT. ISOLATED MODERATE CONVECTION CONTINUES TO FLARE WITHIN 30 NM OF THE NORTHERN PORTION OF THE WAVE AXIS. ...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... THE MONSOON TROUGH IS ANALYZED FROM E TO W ACROSS PANAMA AND CONTINUES ALONG THE PACIFIC COAST OF COSTA RICA GOING OFFSHORE AT 10N86W...AND CONTINUES NW THROUGH AN EMBEDDED AND PERSISTENT 1007 MB SURFACE LOW PRESSURE CENTER NEAR 12N91W. THE MONSOON TROUGH THEN TURNS SW TO 09N100W...THEN NW TO 13N111W...THEN SW TO 11N121W WHERE SCATTEROMETER WINDS INDICATE A TRANSITION TO AN ITCZ WHICH CONTINUES W TO 12N131W...THEN SW TO 09N140W. ISOLATED MODERATE AND STRONG CONVECTION IS OBSERVED WITHIN 120 NM EITHER SIDE OF A LINE FROM 07N80W TO 15N98W. SCATTERED MODERATE ISOLATED STRONG CONVECTION IS OBSERVED S OF THE MONSOON TROUGH AND ITCZ WITHIN 90 NM EITHER SIDE OF A LINE FROM 08N108W TO 11N120W TO 06N140W. SIMILAR CONVECTION IS NOTED OVER AND TO THE N OF THE ITCZ WITHIN 90 NM EITHER SIDE OF A LINE FROM 12N117W TO 14N127W TO 10N140W. ...DISCUSSION... GULF OF TEHUANTEPEC...THE NORTHERLY NOCTURNAL DRAINAGE FLOW ACROSS THE GULF OF TEHUANTEPEC IS EXPECTED TO INCREASE TO 15-20 KT LATE EACH NIGHT THROUGH SUNRISE EACH MORNING THROUGH EARLY NEXT WEEK. THE NOCTURNAL DRAINAGE IS LIKELY TO INCREASE TO 20-25 KT LATE TUE NIGHT AND WED NIGHT AS THE LOW PRESSURE CENTER PREVIOUSLY DESCRIBED DEEPENS TO THE SE OF THE GULF OF TEHUANTEPEC AND INCREASE THE PRESSURE GRADIENT ACROSS THE ISTHMUS OF TEHUANTEPEC. LONG PERIOD NW SWELL IS EXPECTED TO REACH THE FAR NW PORTION OF THE DISCUSSION AREA TONIGHT IN THE FORM OF COMBINED SEAS OF 8-12 FT. THESE SEAS WILL PROPAGATE SE ACROSS THE DISCUSSION AREA REACHING THE PACIFIC COAST OF THE NORTHERN BAJA PENINSULA LATE SUN...AND SPREAD AS FAR SE AS 20N110W LATE MON NIGHT. THE SEAS ARE EXPECTED TO QUICKLY SUBSIDE ACROSS MOST OF THE AREA ON MON. ANOTHER BATCH OF NW SWELL WILL PROPAGATE SE REACHING THE FAR NW PORTION ON THE DISCUSSION AREA BY EARLY TUE WITH SEAS BUILDING 8 TO 11 FT AGAIN ACROSS THE DISCUSSION WATERS NW OF A LINE FROM 32N122W TO 25N140W ON WED NIGHT. THESE ENHANCED SEAS MAY REACH THE NORTHERN BAJA CALIFORNIA PENINSULA ON THU NIGHT. $$ NELSON